Answer:
(1,1)
Step-by-step explanation:
1=-2(1)+3
1= -2 +3
1=1
1=-4(1)=5
1=-4=5
1=1
The main idea here is to "translate" the words into maths.
First we need to identify the unknowns and label these.
We need to know the number if dimes and the number of quarters. So lets say
x: number of dimes
y: number of quarters
Now lets write equations from the written problem.
We know that there are 36 coind total, thus:
x + y = 36
We also know that the coins total 5.85 dollars, but it is better to count in cents, that is 585 cents.
x are the number of dimes, their value is x*10
y are quarters with value of y*25
thus:
10x+25y=585
We have two equations and two unknowns now, that needs to be solved to get the answer.
x + y = 36
10x+25y=585
Answer:
The requirements for the hypothesis test does satisfied the method for testing the claim that from two population proportions the rate of polio is less for children given the salk vaccine.
Step-by-step explanation:
The percentage of children in the treatment group was:
(201229/401974)*100 = 49.9%
The percentage of children given placebo was:
(200745/401974)*100 = 50.1%
The percentage of children that developed polio in the treatment group:
(33/200745)*100 = 0.0164%
The percentage of children that developed polio in the placebo group:
(115/201229)*100 = 0.0571%
The percentage difference between the two group:
((0.0571-0.0164)/0.0571) = 61.62%
Therefore:
The amount of children used for each group was almost divided into half of the total amount of children. The test revealed although very small percentages of the both group developed polio, 68.62% more children given placebo than the children that was given the salk vaccine. Therefore, the study shows that the rate of polio is less for children given the salk vaccine and the the hypthesis test is satisfied.
There's only information to answer question C.
We can only know that 32 marbles were chosen. (yellow and black)
Why?
To answer the first two questions (a and b), we need to know the total number of marbles, so, we can only answer the last question (c).
We know that 7/10 of the 20 yellow marbles were chosen.
So, calculating we have:
Also, we know that 18 black marbles were chosen, so, the total of marbles chosen is equal to 32 (yellow marbles and black marbles)
Have a nice day!
